2008 Annual Monitoring Report (pdf 10.9MB) - Bolsa Chica ...

Bolsa Chica Lowlands Restoration Monitoring
2008 Annual Report
meters on both the starboard and port channels to cover a 40-m wide swath. Following completion of
the survey, sidescan sonar traces were geographically registered, plotted on the geo-rectified aerial
image described above, and the eelgrass digitized to calculate the amount of coverage and show its
distribution.
Cordgrass (Spartina foliosa) harvested from upper Newport Bay was transplanted by M&A and
agency and community volunteers into the FTB on August 21 and 22, 2007. It was planted as both
plugs with native sediment and as bundles of individual bare-root stems in 45x5m blocks at 14 sites
along the northeastern and western shore of the FTB, including Rabbit Island. A total of 0.3 ha (0.7
acre) of cordgrass was transplanted. The distribution of cordgrass in the FTB was mapped one year
later on August 20 and 21, 2008 by walking the perimeter of the cordgrass patches at each transplant
site with a hand-held differential GPS (dGPS) unit. Groups of plants that were less than one meter
apart were mapped as a single patch. Plants more than one meter from other plants were mapped
individually. The height of growing shoots was measured at five locations within each site and the
number of shoots growing within five randomly placed 1-m 2 quadrats was counted at each site.
Quadrats that fell within a bare spot between plants mapped as a patch were recorded as zeros and
factored into the site average.
A photo of each cordgrass transplant site was taken from the west end of the transplant transect
looking roughly eastward. These photos will later be compared to photos taken from the same points
during the next annual survey in August 2009.
Salt Marsh Transect Monitoring
Nineteen permanent vegetation transects were established in 2008 at Bolsa Chica: three at Rabbit
Island, four on the east and north shore of the FTB, three in the west MTB, three in the central MTB,
three in the east MTB, and 3 in the Muted Pocket Marsh (Figure 1-2). The 50-meter transects were
positioned to characterize a range of elevations within the marsh and the endpoints each marked with
labeled stakes and recorded using a dGPS. The coordinates for the transect endpoints are listed in
Appendix 1-B.
On August 14 and 21, 2008, each transect was surveyed by stretching a
fiberglass measuring tape between the stakes and using a line-intercept
method to document the percent cover of plant species and bare
ground/open water. The presence of individual plant species was
recorded for each meter along the 50-meter transect, including a notation
of which species was dominant if there were multiple species. Plants and
bare ground/open water were recorded only if a part of the plant or bare
space fell underneath the vertical plane of the measuring tape.
Additionally, a list of all species observed on each transect within one
meter on either side of the transect was recorded. The canopy height was
recorded at five points randomly selected along each transect and a
photograph of each transect was taken from a fixed point to allow direct
non-quantitative comparison of change over time when repeat photos are
taken in subsequent years.
Transect monitoring.
The collected data were assessed to determine the percent cover of native and non-native species, both
with and without overlap, on each transect within each survey area. The presence of multiple species
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